Unable to create database through PHP.

I'm trying to create a database in my wamp server but every time the following error appears:
"Error Creating database Access denied for user ''@'localhost' to database 'my_database'"
I've checked from the cmd prompt and my user is root@localhost. I tried to create the same database from phpmyadmin and it was created.
Can anyone tell me what the real problem is?

See original post by saadi123